蓄电池放电是将化学能转变为电能的过程,其电流流动方向为()。
A.正极→负极→负载
B.负极→负载→正极
C.正极→负载→负极
D.负极→正极→负载
参考答案:C
读一读,写一写。
1. How much is the T-shirt?
.
2. How much is the skirt?
3. How much are the shorts?
4. How much are the pants?
南宋时,指南针经阿拉伯人传达到()。
A.美洲
B.西亚
C.非洲
D.欧洲